#region The MIT License
// The MIT License
// 
// Copyright (c) 2009 octalforty studios
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
#endregion
using System;
using System.Collections.Generic;
using octalforty.Componento.Shared.SemanticModel;
using octalforty.Componento.Util;

namespace octalforty.Componento.ComponentModel.Installation
{
    public class PathMappingSelector
    {
        public PathMapping SelectPathMapping(IEnumerable<PathMapping> pathMappings, CliEnvironment environment, IsaType isa)
        {
            if(pathMappings == null)
                return null;

            //
            // Rules are as follows:
            //  - If environment is fully qualified (includes CLI & version), we first look for exach match (
            //    (including ISA) and take first matched element.
            //  - If environment only has CLI type, look for path mappings with matching CLI and ISA
            PathMapping matchedMapping = 
                Algorithms.First(
                    Algorithms.Filter(pathMappings, 
                        delegate(PathMapping pm)
                            {
                                return pm.Cli.Cli == environment.Cli && pm.Isa == isa &&
                                    ((environment.Version == null || pm.Cli.Version == null) ? 
                                        true :
                                        IsSubsetOf(environment.Version, pm.Cli.Version));
                            }));

            return matchedMapping;
        }

        private bool IsSubsetOf(Version v1, Version v2)
        {
            return v1.ToString().Equals(v2.ToString()) || v1.ToString().StartsWith(v2.ToString());
        }
    }
}
